1,132 Pneumatic (ATA 36) service difficulty reports for the Boeing 737 (all variants) — 0.4% of all reported difficulties.
Most reported components
- VALVE 203
- REGULATOR 189
- SHUTOFF VALVE 124
- UNKNOWN 97
- CONTROL VALVE 94
- SENSOR 60
- MODULATING VALVE 44
- LINK 25
- SENSE LINE 23
- LINE 18
- PRECOOLER 16
- DUCT 16
- PRESSURE VALVE 13
- WARNING SYSTEM 11
- REGULATOR VALVE 10
Report counts reflect fleet size and reporting activity, not relative safety or reliability. Source: FAA Service Difficulty Reporting System (public domain).